The invention integrates technologies relating to cervical immobilization and to therapeutic induction of mild cerebral hypothermia by transcutaneous cooling of oxygenated blood flowing through carotid arteries.
Brain injuries, such as those produced by blunt trauma or ischemic attack, can produce lasting damage and require long-term treatment or care. Often, brain injuries produced by blunt trauma are suffered by the young, and any resulting disabilities or conditions can be expensive to treat and can require long-term care lasting nearly a lifetime. Brain injuries in general are expensive to treat, but lasting injuries, especially in the young, can impose significant societal burdens.
Brain cooling, i.e., reducing brain temperatures by as little as one or two degrees Celsius, produces a neuroprotective effect against deleterious responses associated with brain injuries. The mild cerebral hypothermia inhibits the release of neuroexcitetory amino acids (e.g., aspartate and glutamine), thereby interrupting the cascading effects of the inflammatory response. The neuroprotective effect is most pronounced if brain cooling is effected as soon as possible following an injury.
One way of cooling the brain is by withdrawing heat from the blood supply to the brain. For example, a mild cerebral hypothermia can be induced by transcutaneous conduction of heat from one or both of the carotid arteries accessible through the carotid triangles of the neck. Endothermic heat extractors positioned over the carotid triangles can be used to cool blood flowing into the brain.
Although the neuroprotective effects of even mild cerebral hypothermia have been well documented, along with the importance of initiating such cooling as soon as possible following a brain injury, protocols for first responders generally do not incorporate effective procedures for initiating brain cooling. For example, blunt head trauma is often associated with the risk of cervical injury, and the routine application of conventional cervical immobilization collars can block effective cooling of neck tissue close to the carotid arteries. Even if early brain cooling is a treatment option for cases of obvious blunt head trauma, other brain injuries can be difficult to detect on site, especially if there are few outward signs or the inflammatory response is slow to develop.